Add insert method to Quantity
Change insert implementation to use np.insert per @mhvk
Add tests of Quantity.insert
Update CHANGES.rst
Fix some minor issues in review and travis tests
Simplify tests by using float quantities
Merge pull request #3049 from taldcroft/quantity-insert

Add insert method to Quantity
Correct Quantity.list to .tolist, overriding the correct ndarray method